2. NOTICE Medicine is an ever-changing science. As new research
and clinical experience broaden our knowl- edge, changes in
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3. Warren P. Bishop, MD Professor of Pediatrics Carver College
of Medicine University of Iowa Director, Division of
Gastroenterology University of Iowa Childrens Hospital Iowa City,
Iowa EDITOR New York Chicago San Francisco Lisbon London Madrid
Mexico City Milan New Delhi San Juan Seoul Singapore Sydney Toronto
Gastroenterology PEDIATRIC PRACTICE Medical
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5. This book is dedicated to the memory of my parents and to my
wife and life-long partner, Gail Bishop. My mother and father
provided me with a love of reading and learning, and gave me
innumerable opportunities throughout my growing years. None of this
would have been possible without that great start in life. My last
30-plus years have been spent in partnership with my wife. We
struggled....
8. 22 Polyps and Tumors of the Intestines . . . . . . . 319
Warren P. Bishop Section 4: Disorders of the Liver / 329 23 Biliary
Atresia . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
330 Melissa Leyva-Vega and Barbara A. Haber 24 Viral Hepatitis . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . 341 Jos R.
Romero and Judith A. OConnor 25 Wilsons Disease. . . . . . . . . .
. . . . . . . . . . . . . . . . . 356 Karan McBride Emerick 26
Alpha-1-antitrypsin Deciency. . . . . . . . . . . . . 367 Jeffrey
H. Teckman 27 Autoimmune Liver Disorders . . . . . . . . . . . . .
. 376 Tyler M. Burpee and Karen F. Murray 28 Metabolic and
Drug-induced Liver Disease. . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . 385 Judith A. OConnor 29 Liver Transplantation .
. . . . . . . . . . . . . . . . . . . . . 403 Yumirle Turmelle and
Ross W. Shepherd 30 Liver Failure and Portal Hypertension . . . . .
. 418 Elizabeth Mileti and Philip Rosenthal Section 5: Disorders of
the Pancreas / 427 31 Acute and Chronic Pancreatitis . . . . . . .
. . . . . 428 Mark E. Lowe 32 Pancreatic Insufciency and Cystic
Fibrosis. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
441 Aliye Uc INDEX / 453 viii Contents
9. Contributors Eric Chiou, MD Fellow Department of
Gastroenterology and Nutrition Center for Motility and Functional
Gastrointestinal Disorders Childrens Hospital Boston Boston,
Massachusetts Dawn R. Ebach, MD Clinical Assistant Professor
Department of Pediatrics University of Iowa Iowa City, Iowa Steven
T. Elliott, MD Research Fellow Department of Surgery Childrens
National Medical Center Washington, District of Columbia Surgery
Resident Department of Surgery University of California Davis
Medical Center Sacramento, California Karan McBride Emerick, MD,
MSCI Associate Professor Department of Pediatrics University of
Connecticut School of Medicine Hartford, Connecticut Robert D.
Baker, MD, PhD Professor Department of Pediatrics University at
Buffalo The State University of New York Buffalo, New York Susan S.
Baker, MD, PhD Professor Department of Pediatrics University at
Buffalo The State University of New York Buffalo, New York Sanjoy
Banerjee, MD, MPH Assistant Professor of Pediatrics The University
of Toledo Health Science Campus Pediatric Gastroenterologist Toledo
Childrens Hospital/Promedica Physician Group Toledo, Ohio Warren P.
Bishop, MD Professor and Director Division of Gastroenterology
Department of Pediatrics University of Iowa Carver College of
Medicine Lowa City, Iowa Tyler M. Burpee, MD Assistant Professor
Department of Pediatrics University of Washington School of
Medicine Seattle, Washington
10. x Contributors Thomas Flass, MD Fellow Department of
Gastroenterology, Hepatology, and Nutrition The Childrens Hospital
Aurora, Colorado Benjamin D. Gold, MD, FACG, FAAP Adjunct Professor
Department of Pediatrics Emory University School of Medicine
Atlanta, Georgia Barbara A. Haber, MD Associate Professor
Department of Pediatrics The Childrens Hospital of Philadelphia
Philadelphia, Philadelphia Eyad Hanna, MD Clinical Assistant
Professor Department of Pediatric Gastroenterology and Hepatology
University of Iowa Iowa City, Iowa Edward J. Hoffenberg, MD
Professor of Pediatrics University of Colorado School of Medicine
Director, Program for Pediatric Inammatory Bowel Diseases The
Childrens Hospital 13123 East 16th Avenue Aurora, Colorado 80045
Subra Kugathasan, MD Professor Department of Pediatrics Emory
University Atlanta, Georgia Melissa Leyva-Vega, MD Fellow Division
of Gastroenterology, Hepatology, and Nutrition The Childrens
Hospital of Philadelphia Philadelphia, Philadelphia B U.K. Li, MD
Professor Division of Pediatric Gastroenterology, Hepatology and
Nutrition Department of Pediatrics The Medical College of Wisconsin
Milwaukee, Wisconsin Chris A. Liacouras, MD Professor of Pediatrics
Department of Gastroenterology, Hepatology, and Nutrition
University of Pennsylvania School of Medicine Philadelphia,
Philadelphia Jenifer R. Lightdale, MD, MPH Assistant Professor
Department of Pediatrics Harvard Medical School Boston,
Massachusetts Mark E. Lowe, MD, PhD Professor Department of
Pediatrics University of Pittsburgh Pittsburgh, Philadelphia
Michael A. Manfredi, MD Instructor Department of Pediatrics Harvard
Medical School Boston, Massachusetts Jonathan E. Markowitz, MD,
MSCE Associate Professor Department of Clinical Pediatrics
University of South Carolina School of Medicine, Greenville
Greenville, South Carolina John Meehan, MD Associate Professor
Department of Surgery Division of Pediatric Surgery University of
Washington Seattle, Washington
11. Contributors xi Elizabeth Mileti, DO Clinical Fellow
Department of Pediatric Gastroenterology, Hepatology and Nutrition
University of California, San Francisco San Francisco, California
Hayat Mousa, MD, FAAP Associate Professor Medical Director of the
Motility Center Department of Pediatrics Division of Pediatric
Gastroenterology Ohio State University Columbus, Ohio Karen F.
Murray, MD Professor Department of Pediatrics Division of
Gastroenterology, Hepatology, and Nutrition University of
Washington School of Medicine Seattle, Washington Richard J. Noel,
MD, PhD Assistant Professor Department of Pediatrics Medical
College of Wisconsin Milwaukee, Wisconsin Samuel Nurko, MD, MPH
Associate Professor Department of Pediatrics Harvard Medical School
Division of Gastroenterology Childrens Hospital Boston Boston,
Massachusetts Judith A. OConnor, MD, MS Associate Professor
University of Arkansas for Medical Sciences Section of
Gastroenterology, Nutrition & Hepatology Department of
Pediatrics Arkansas Childrens Hospital 1 Childrens Way Little Rock,
Arkansas 72202 Bharani Pandrangi, MD Fellow Department of Pediatric
Gastroenterology University of Iowa Iowa City, Iowa Dinesh S.
Pashankar, MD, MRCP Associate Professor Department of Pediatrics
Yale University School of Medicine New Haven, Connecticut Uma
Padhye Phatak, MD Fellow Department of Pediatric Gastroenterology
Yale University School of Medicine New Haven, Connecticut Graeme
Pitcher, MBBCh, FCS(SA) Clinical Associate Professor Division of
Pediatric Surgery University of Iowa Iowa City, Iowa Riad M.
Rahhal, MD Assistant Professor Department of Pediatrics University
of Iowa Iowa City, Iowa Jose R. Romero, MD, FAAP Horace C. Cabe
Endowed Professor of Pediatrics University of Arkansas for Medical
Sciences Section Chief, Pediatric Infectious Diseases Arkansas
Childrens Hospital 1 Childrens Way Little Rock, Arkansas 72202
Rachel Rosen, MD, MPH Assistant Professor Department of Pediatrics
Harvard Medical School Center for Motility and Functional
Gastrointestinal Disorders Childrens Hospital Boston Boston,
Massachusetts Philip Rosenthal, MD Professor of Pediatrics and
Surgery Department of Pediatrics University of California, San
Francisco San Francisco, California
12. Anthony D. Sandler, MBChB, FACS, FAAP Diane and Norman
Bernstein Chair, Professor, and Chief Department of Pediatric
Surgery Childrens National Medical Center George Washington
University Medical Center Washington, District of Columbia Yutaka
Sato, MD Professor Department of Radiology University of Iowa Iowa
City, Iowa Rebecca Scherr, MD Fellow Department of Pediatric
Gastroenterology Emory University Atlanta, Georgia Ross W.
Shepherd, MD, FRACP Professor Department of Pediatrics Washington
University School of Medicine St. Louis, Missouri Joel Shilyansky,
MD, FACS, FAAP Associate Professor Department of Surgery University
of Iowa Carver College of Medicine Iowa City, Iowa Achint K. Singh,
MD Fellow Department of Radiology University of Iowa Iowa City,
Iowa Jeffrey H. Teckman, MD Associate Professor Department of
Pediatrics and Biochemistry and Molecular Biology St. Louis
University School of Medicine St. Louis, Missouri Yumirle P.
Turmelle, MD Assistant Professor Department of Pediatrics
Washington University School of Medicine St. Louis, Missouri Aliye
Uc, MD Associate Professor of Pediatrics Associate Professor of
Radiation Oncology Carver College of Medicine University of Iowa
University of Iowa Childrens Hospital 200 Hawkins Drive, 2868 JPP
Iowa City, Iowa Narayanan Venkatasubramani, MD, MRCP, MBBS
Assistant Professor Division of Pediatric Gastroenterology,
Hepatology and Nutrition Department of Pediatrics The Medical
College of Wisconsin Milwaukee, Wisconsin xii Contributors
13. This textbook was conceived as a resource for all
healthcare professionals who care for children. At its conception,
the target audience was to consist of primary care physicians, but
it will clearly be equally valuable to medical students, residents
in family medicine, pediatrics, and surgery, specialists in many
elds who may be confronted with a child experiencing
gastrointestinal symptoms, and a variety of allied health
professionals. We have endeavored to supply a concise, illustrated,
and current reference on gastrointestinal and liver disorders
designed for all physicians who care for children. Many colorful
illustrations are designed to enhance readability and improve
understanding of complex topics. The rst section deals with
evaluation of common symptoms emphasizing the differential
diagnosis and evaluation of the symptoms, as well as treatment of
common causes. Disease chapters follow a similar practical
approach, and are supplemented by several chapters on diagnostic
modalities. Each chapter contains a list of references for the use
of the reader in further exploration of selected topics. This is a
book that is dense with practical information. It is beautifully
illustrated, readable, portable, and, most importantly, highly
informative and up-to-date. Warren P. Bishop Preface
14. This page intentionally left blank
15. This book would never have occurred without the support of
many colleagues who trained me, especially Dr. Martin H. Ulshen,
who was my mentor during fellowship training at the University of
North Carolina and a role model for my career. Dr. Colin Rudolph
has generously encouraged me in the writing of this book, and his
example as a successful editor of a major textbook of pediatrics
and a leader of a large academic gastroenterology group has been
inspirational. The many ne chapter contributors have my gratitude
for their hard work, dedication to providing a quality product, and
their cheerful cooperation with the sometimes arduous editorial
process. The North American Society of Pediatric Gastroenterology
and Nutrition has been an enormous benet to my career, providing
networking, education, innumerable role models, and career growth
opportunities. All of the authors of this book are members of that
ne organization, which tirelessly advocates for the advancement of
childrens healthcare. Finally, I wish to thank my editor at McGraw
Hill, Alyssa Fried, who has been a tireless cheerleader, advocate,
and friend. She has been indispensable in the production of the
book. Acknowledgments
16. This page intentionally left blank
17. SECTION 1 Symptoms and Assessment 1. Abdominal Pain 2.
Vomiting 3. Feeding and Swallowing Disorders 4. Diarrhea 5.
Constipation 6. Gastrointestinal Bleeding 7. Jaundice and Neonatal
Cholestasis 8. Nutrition
18. CHAPTER 1 Abdominal Pain Sanjoy Banerjee DEFINITION AND
EPIDEMIOLOGY Abdominal pain is a common complaint in pediatric
population, often resulting in unscheduled ofce or emergency room
visits. This symptom can be acute, recurrent, or chronic. Acute
abdominal pain generally refers to pain that has been present for
24 hours. When the presen- tation is acute, the challenge for the
evaluating physi- cian is to differentiate potentially
life-threatening and serious medical conditions from benign
self-limited ones. The frequency of surgical intervention in
patients presenting with acute abdominal pain is around 1%,1 but
the possibility of overlooking a serious organic eti- ology is a
cause of concern to evaluating physicians and families. Children
are considered to have recurrent or chronic abdominal pain if they
have experienced at least three bouts of abdominal pain, severe
enough to affect activities, over a period of at least 3 months.
Though this denition was initially used by Apley and Nash2 as the
entry criteria for their descriptive study, it later became a term
to describe all children with abdominal pain without known organic
etiology. Recurrent abdom- inal pain (RAP) should be used as a
description rather than as a diagnosis. RAP may occur in functional
abdominal pain (FAP; see below), but this pattern of discomfort can
also occur with organic disease.3 Func- tional gastrointestinal
disorders (FGID) include a com- bination of chronic and/or
recurrent symptoms not explained by known biochemical or structural
abnor- malities. According to Rome III criteria, symptoms must
occur at least once per week for at least 2 months before making a
diagnosis of FGID.4 In a study of 227 patients with recurrent and
chronic abdominal pain, only 76 (33%) were found to have well-dened
organic etiologies.5 Abdominal pain accounts for 24% of all
pediatric ofce visits.6 In a study by Hyams et al., 13% of middle-
school students and 17% of high-school students experienced weekly
abdominal pain. In that study, approximately 8% students saw their
physician for abdominal pain evaluation in the previous year.7
InApley and Nash original study involving 1000 children in pri-
mary and secondary schools, 10.8% of children had RAP, with a
female preponderance (female to male ratio of 1.3:1).2 In that
survey, the age distribution was also examined. Ten to 12% of males
aged 510 years had RAP, followed by decline in prevalence and a
later peak at age 14 years. Females showed a sharp rise in
prevalence after age 8 years and by age 9 years 25% of this group
experi- enced RAP. The long-term outcome of patients with FGID is
not known, but studies indicate patients with history of chronic
abdominal pain that began in child- hood and treated by a
subspecialist are more likely to have lifelong psychiatric problems
and migraine head- aches.3 Genetic factors and early life events
may have a role in the pathogenesis of chronic abdominal pain.
Family History There is a higher prevalence of alcoholism,
psychiatric disorders,somatization disorders,migraine,and chronic
pain symptoms among family members. Familial clus- tering is often
seen in patients with FGID. Subjects with FGID, in a study by Locke
et al., had an increased risk of reporting a rst-degree relative
with abdominal pain and/or bowel distrurbance.8 Possible
explanations of familial clustering could include both
environmental and/or genetic factors.
19. CHAPTER 1 Abdominal Pain 3 bers. The C bers are located in
visceral peritoneum, mesentery, and viscera. Signals transmitted by
these bers result in dull, poorly localized pain. Because pain bers
from abdominal organs communicate bilaterally with more than one
adjacent spinal level, visceral pain is often felt in midline as a
poorly localized sensation. The location of abdominal pain is
determined by the developmental origin of the affected viscera
(Table 12). A- bers are found in the somatic structure surround-
ing the viscera: the abdominal wall, retroperitoneal skeletal
muscles, and parietal peritoneum. These bers have small receptive
fields and nociceptive signals through these bers result in sharp,
well-localized sensations. Patterns of Pain Understanding the types
of pain bers and their dis- tribution is important to understanding
clinical phe- nomena. Visceral pain from most of the gut is poorly
localized and difcult to characterize due to activation Early Life
Events Noxious stimuli experienced during the neonatal period, when
nociceptive neuronal circuits are formed, may result in decreased
pain thresholds later in life. Respira- tory distress, neonatal
infections, colic, neonatal surgeries, or congenital hydronephrosis
is reported in approximately 20% patients with chronic abdominal
pain.9 PATHOGENESIS Pain originating in the gut is initiated by
stimulation of receptors (nociceptors) sensitive to specic
mechanical and chemical stimuli. Stretch and the contractile force
are the principal mechanical stimuli. Other stimuli, even crushing,
cutting, or tearing of the viscera, do not cause pain. Mechanical
nociceptors are located in the muscu- laris layers, between the
muscularis layer and submucosa of hollow viscera, in the serosa of
solid organs, and in the mesentery. Various intra-abdominal
processes cause pain by stimulating these mechanical nociceptors
(Table 11).Chemical nociceptors are present within the mucosa and
submucosa of the gut. Various triggers such as inammation, tissue
ischemia and necrosis, and radia-
tioninjurystimulatethesereceptorsviainjury-associated release of
mediators, such as prostaglandins, leukot- rienes, bradykinin,
serotonin, substance P, calcitonin gene-related peptide, histamine,
and H and K ions.10 These substances and mast cell proteases such
as 5-HT3 receptors have the potential of elevating the sensitivity
of intestinal sensory nerves. Postinfectious irritable bowel
syndrome (IBS) develops in a signicant percent- age of individuals
after an acute bout of infectious enteritis. It is unclear if this
is the result of exposure of neural and glial elements of the
enteric nervous system to the elevated levels of these inammatory
mediators. Afferent nociceptive sensory neurons are either slow,
unmyelinated C bers or fast, myelinated A- Examples of Stimulation
of Mechanical Nociceptors Stimulus Event Rapid distension of hollow
viscus Smooth muscle contractions Rapid stretching of capsule of
solid organ Torsion of the mesentery Traction on mesentery or
mesenteric vessels Intestinal obstruction Biliary, renalcolic
Hepatic congestion Cecal volvulus Retroperitoneal mass Primary
causes of visceral abdominal pain are distension and excessively
strong contractions of the musculature of the digestive tract.
Hypersensitivity of the mechanoreceptors that detect stretch and
contractile force leads to increased nociceptive afferent
stimuli,as seen in patients with functional gastrointestinal
disorder. Table 11. Visceral Pain Perception and Embryological
Origin of Organ Embryological origin Pain localization Foregut:
stomach, liver, biliary system, pancreas, spleen, duodenum
Epigastrium Midgut:jejunum,ileum,appendix,and colon to the level of
midtransverse colon Periumbilical Hindgut: distal transverse,
splenic exure, descending, and sigmoid colon Hypogastrium, lower
midline Patterns of visceral pain.Visceral pain is felt in the
midline in the epigastric, periumbilical,or hypogastric areas,and
this pattern reects the ontogenic origin of the involved organs
from the foregut,midgut,or hindgut,respectively. Table 12.
20. 4 Section 1: Symptoms and Assessment may participate in the
sensitization of peripheral nocice- ptors. The autonomic nervous
system plays a role in pain modulation and the associated
behavioral and emotional responses to pain. Secondary autonomic
effects such as sweating, perspiration, and pallor often accompany
vis- ceral pain. The emotional aspects of pain are interpreted in
the limbic system and frontal cortex through projec- tion from the
brain stem (reticular formation nucleus). Thus, it is important to
conceptualize pain as a function of two phenomena: one providing
the sensory informa- tion from afferent nociceptors and the other
modulating the sensation and producing emotional, cognitive, phys-
iological, and behavioral responses. The functional connections
between the brain and the spinal cord result in both inhibitory and
excit- atory modications of afferent pain impulses. There are
inhibitory mechanisms at the level of the spinal cord (inhibitory
interneurons of substantia gelatinosa). Inhibitory neurons
originating in mesencephalon, periventricular gray matter, and
caudate nucleus par- ticipate in descending inhibition, and have
dampening effect on pain.11 Pain can be dened as nociceptive when
it results from stimulation of peripheral nociceptors by mechanical
or chemical stimuli (stretch, local injury, or inammation). Changes
in the pain pathway can result in neuropathic pain from aberrant
signaling or altera- tion in inhibitory central processes.
Neuropathic pain can happen without stimulation of peripheral
nociceptors. The pathophysiology of chronic,recurrent abdom- inal
pain is not completely understood. There is a of unmyelinated C
bers reporting to several spinal lev- els at once. A good example
of this is the pain associated
withCrohnsdiseaseofthesmallintestine.Somatoparietal pain results
from stimulation of the parietal peritoneum, and is more intense
and somewhat better localized than visceral sensation. Somatic pain
occurs when somatic structures, innervated by A- bers, are injured
or inamed. In some cases, as in acute appendicitis, pain begins as
poorly localized, dull periumbilical discom- fort due to inammation
of the inner layers of the appendix, and then becomes progressively
more severe and better localized with subsequent inammation of rst
the parietal peritoneum and then the adjacent abdominal wall.
Referred pain is felt in a body area that has its somatic
innervation from the same spinal seg- ments receiving visceral pain
bers from the diseased organ. It is usually well localized, as in
left shoulder pain from myocardial infarction. Common patterns of
referred pain in acute abdominal processes are shown in Figure 11.
Pain Perception Afferent nerves mediating painful stimuli from
abdomi- nal viscera follow the distribution of the autonomic ner-
vous system and have cell bodies in dorsal root ganglia. Although
nociceptive bers run together with the sym- pathetic bers through
sympathetic ganglia (celiac, superior mesenteric, and inferior
mesenteric ganglia), they are not part of the sympathetic nervous
system. The sympathetic nervous system does not convey pain, but
FIGURE 11 Patterns of referred pain. The diagram shows important
skin areas of referred visceral pain. Adapted from reference 19
Diaphragm Gallbladder Appendix Esophagus Heart Pancreas Stomach
Kidney Ureter Urinary bladder Gallbladder
21. CHAPTER 1 Abdominal Pain 5 urgent interventions. The most
important component of the evaluation process is a carefully taken
history and a detailed physical examination.Selective use of
appropriate radiological and laboratory investigations may be
required to establish a specic diagnosis. Both the evaluating
physi- cian and the caregivers, however, must realize that the
diagnosis may remain uncertain despite a thorough initial
evaluation. In the absence of an obvious indication for surgery,
patients with concerning acute symptoms should be observed in the
hospital or emergency department with serial abdominal examinations
to clarify any diag- nostic uncertainty. Infants and younger
pediatric patients are especially challenging,as they are unable to
describe or localizepain.Painisofteninferredbasedoninconsolability
or crying with abdominal palpation. A school-age child can usually
characterize the location, intensity, and tem- poral progression of
pain with reasonable accuracy. Acute Abdominal Pain History
Important details of the history include pattern of onset,
progression, location, intensity and character, aggravating and
alleviating factors of abdominal pain, and associated symptoms.Key
historical variables include age and gender complex interplay of
psychosocial and physiological fac- tors that leads to disturbed
gastrointestinal function. Physiological alterations can happen at
the level of gut nociceptors, spinal afferents, central autonomic
relay sys- tem, or pain centers in the brain. Failure of central
down- regulation and pain amplication by psychosocial factors lead
to visceral hypersensitivity. Key mediators of gut function, such
as serotonin (5-HT) and corticotropin- releasing factor (CRF), may
modulate input from central nervous system along the brain gut
axis, and cause altered intestinal motility and visceral
hypersensitivity.11,12 Important psychosocial factors contributing
to pain are lack of a social support system,anxiety-provoking
events, a dysfunctional or abusive relationship, family attitude
toward illness, and lack of coping skills. Pathophysiolog- ical
mechanisms implicated in chronic,recurrent abdom- inal pain are
summarized in Figure 12. CLINICAL PRESENTATIONS General Approach to
Pain The evaluating physicians role is to establish an accurate
diagnosis in an expeditious manner. The immediate goal is to
identify life-threatening emergencies that require Abnormal
perception Psychosocial issues Altered Gl motility Dietary factors
Coping style Genetic factors Early life pain experiences Abnormal
intestinal permeability Small intestinal bacterial overgrowth
Sensitized visceral nociceptors 5-HT CRF Expectation for pain
Environmental factors Secondary gains Post infectious Inflammatory
bowel disease Celiac disease Inflammatory processes FIGURE 12
Biopsychosocial model of chronic abdominal pain. Nociceptive input
to the brain comes from sensitized enteric nervous system. Genetic,
developmental, environmental, and psychological fac- tors, and
coping skills modify the pain experience. 5-HT =
5-hydroxytryptamine; CRF = corticotrophin- releasing factor. Image
courtesy of Sumit Banerjee, Toledo, Ohio. Adapted from reference
10.
22. 6 Section 1: Symptoms and Assessment there is metabolic
acidosis as in diabetic ketoacidosis, gastroenteritis with
dehydration, peritonitis, and intes- tinal obstruction. Hypotension
suggests intravascular volume loss (acute gastroenteritis and
abdominal trauma with intra-abdominal hemorrhage), or third- space
loss (volvulus, intussusception, and peritonitis). Abdominal
examination: Abdominal examination is often difcult to perform in a
crying, uncooperative sick infant or child. Young patients are best
examined in their position of comfort, usually in the lap of a
parent. The abdomen should be examined before other
anxiety-provoking examinations (e.g., exami- nation of throat and
ear). The examining physician must make efforts to determine the
degree of abdom- inal tenderness and its location. Severe, diffuse
ten- derness with abdominal wall rigidity is indicative of
peritonitis. Reproducible focal tenderness is indica- tive of
intra-abdominal inammatory process, as with McBurneys point
tenderness in appendicitis, epigas- tric tenderness in acute
pancreatitis, and right upper quadrant tenderness with acute
cholecystitis. Abdom- inal distension is seen with intestinal
obstruction or abdominal mass. Other inspection findings may
include ecchymoses (abdominal trauma), scars (prior abdominal
surgery and associated adhesions), her- nias, and visible
intestinal peristalsis (intestinal obstruction or gastroenteritis).
Extra-abdominal findings: Important diagnostic clues are often
obtained from extra-abdominal ndings. A characteristic rash is seen
in HenochSchnlein of the patient, history of abdominal trauma or
prior abdominal surgery, and a thorough review of system. Common
causes of acute abdominal pain have character- istic presentations
and knowledge of these characteristics is essential for an
expeditious diagnosis (Table 13). Physical examination Careful
systemic and abdominal examinations are essential for accurate
diagnosis. Physical examination ndings must be interpreted by
taking the patients his- tory and age into account. Examination of
external genitalia, anus, and rectum is recommended as part of
evaluation for abdominal pain. Pelvic examination is important in
sexually active female patients. Key elements of the physical
examination are as follows: Appearance: Appearance, hydration
status, facial expression, breathing pattern, position in bed, and
degree of discomfort should be carefully assessed. A child
reluctant to move or in a fetal position is likely to have
peritonitis. Patients with pure visceral pain, as in biliary colic
or bowel obstruction, change position fre- quently, often writhing
in pain. Vital signs: Vital signs are useful in assessing hypov-
olemia and provide useful clues for diagnosis. Patients with fever
and acute abdominal pain may have acute gastroenteritis, pneumonia,
pyelonephritis, pharyngi- tis, acute cholecystitis, appendicitis,
or an intra-abdominal abscess. Tachypnea may indicate pneumonia.An
acidotic breathing pattern is seen when Presenting History of
Common Causes of Acute Abdominal Pain Condition: Onset Location
Radiation Associated symptoms and review of systems Appendicitis
Gradual Periumbilical early; RLQ late RLQ Fever, nausea, vomiting
Pancreatitis Rapid Epigastric, back Mid-back Fever, nausea,
vomiting Cholecystitis Rapid RUQ Right scapula Nausea, vomiting,
fever Small bowel obstruction Gradual Periumbilical None Bilious
emesis (high obstruction), feculent emesis (distal obstruction),
h/o trauma, prior abdominal surgery (adhesions) Gastroenteritis
Gradual Periumbilical None Fever, diarrhea bloody stool, vomiting
Pelvic inammatory disease Gradual Pelvic or LQ Upper thigh Fever,
dysuria, vaginal discharge Perforated peptic ulcer Sudden
Epigastric Mid-back Fever nausea, Ruptured ectopic pregnancy Sudden
Pelvic or LQ None Lightheaded, vaginal bleeding Patterns of common
causes of acute abdominal pain.LQ = lower quadrant; RLQ = right
lower quadrant; RUQ = right upper quadrant. Table 13.
23. CHAPTER 1 Abdominal Pain 7 Presence of pallor, growth
retardation, acute weight loss, clubbing, jaundice, peripheral
edema, or signi- cant lymphadenopathy may indicate organic
etiology. It is uncommon to nd signs of autonomic arousal
diaphoresis, tachycardia, or elevated blood pressure in absence of
acute organic causes of abdominal pain. Carnetts test distinguishes
abdominal wall pain from visceral pain. The pain from palpation at
the site of maximal tenderness increases in abdominal wall pain
with raising the head and contracting the rectus abdominis muscle,
whereas in visceral pain it decreases. The closed-eyes sign is
often seen in patients with FAP. These patients will wince with
their eyes closed when the abdomen is palpated, whereas those with
organic etiology keep their eyes open, fearfully antici- pating
pain with abdominal palpation. Inspect the abdomen for scars
(indicative of prior surgery), distension, visible peristalsis,
dilated vessels, or striae. It is important to examine the perianal
area and hernial orices, and perform digital rectal examination.
Reexamination of the patient during acute exacerba- tion of
abdominal pain will often provide important clinical information.
DIFFERENTIAL DIAGNOSIS Acute Abdominal Pain Acute abdominal pain
generally refers to pain that has been present for 24 hours. The
most common causes of the acute abdomen are listed in Tables 14 and
15. A detailed purpura or scarlet fever. Jaundice is observed in
hepa- titis, gallbladder disease, or hemolytic anemia. Evi- dence
of trauma elsewhere may be associated with occult visceral injury.
Chronic or Recurrent Abdominal Pain History If possible,
interrogate the patient directly, using developmentally appropriate
techniques. Ask the patient to localize the pain area with his or
her own hand. Poorly localized pain suggests visceral or functional
etiology. Obtain information about the quality, intensity, dura-
tion, and timing of the pain. Ask about other associ- ated
symptoms, including vomiting, diarrhea, consti- pation, fever,
rectal bleeding, weight loss, joint symptoms, oral ulcers, dysuria,
hematuria, or perianal discharge. These symptoms often indicate an
organic disease. Enquire about aggravating and relieving factors of
the pain, relationship to diet, activity, posture, or psycho-
social stressors. Assess the impact of chronic pain on daily
function- ing. Is the pain debilitating? Has it become the central
focus of the patients life? What is the impact of pain on school
attendance or sports participation? Enquire about the possibility
of sexual or physical abuse, unresolved grief or losses, or
depression. Ask about therapeutic attempts made to relieve
abdominal symptoms and their efcacy. Specically, enquire about the
use of nonsteroidal anti- inammatory drugs, narcotics, or
laxatives. There is no literature showing that pain frequency,
location, timing (postprandial and nocturnal awaken- ing),
severity, and impact on quality of life are able to distinguish
between patients with organic and func- tional disorders. There are
also insufcient data to determine whether the presence of
associated symp- toms such as headache, anorexia, joint pain,
vomiting, nausea, atulence, and altered bowel pattern helps in
distinguishing between organic and functional disor- ders. The
presence of alarm symptoms such as involuntary weight loss, slowing
of linear growth, severe vomiting, gastrointestinal blood loss,
chronic severe diarrhea, unexplained fever, localized right upper
or lower quadrant pain, and family history of inamma- tory bowel
disease suggests a higher probability of organic disease. Physical
examination Carefully note facial expression, body posture, breath-
ing pattern, and interaction of the patient with the accompanying
family members. Abdominal Causes of Acute Abdomen Gastrointestinal
Appendicitis Trauma Incarcerated hernia Intussusception Volvulus
Intestinal obstruction Meckel diverticulitis Necrotizing
enterocolitis Intestinal perforation Inammatory bowel disease Acute
gastroenteritis Constipation Spontaneous bacterial peritonitis
Pancreatic, splenic, hepatobiliary Acute pancreatitis Acute
cholecystitis Acute cholangitis Acute hepatitis Hepatic abscess
Splenic rupture Abdominal wall Rectus abdominis hematoma
Renal/urologic Acute pyelonephritis Nephrolithiasis Testicular
torsion Pelvic Ovarian torsion Ruptured ovarian cyst Pelvic
inammatory disease Ectopic pregnancy Adapted from reference 10.
Table 14.
24. 8 Section 1: Symptoms and Assessment period. Distal
intestinal obstruction syndrome (DIOS), sometimes called meconium
ileus equivalent, is seen in older children with cystic brosis.
They present with ileal obstruction caused by thickened stool.
Early diag- nosis is essential in all cases of small bowel
obstruction to avoid bowel ischemia. High intestinal obstruction is
characterized by frequent bilious emesis and epigastric pain.
Cramping, periumbilical or lower abdominal pain with infrequent
feculent emesis is typical of distal intes- tinal obstruction.
Radiological features of small bowel obstruction are dilated loops
of small bowel, with air uid levels and decompressed distal bowel.
Ultrasonog- raphy is useful for diagnosis of ileocolic
intussusception, with sensitivity approaching 100%.
Ultrasonographic ndings suggestive of volvulus are dilated
duodenum, an abnormal position of the superior mesenteric vein, and
a whirlpool sign of volvulus caused by the vessels twisting around
the base of the mesenteric pedicle. Abdominal CT and enteroclysis
often help with diag- nosing and locating the site of obstruction
in patients with strictures, adhesions, or other focal lesions. A
con- trast (air or barium) enema is useful for diagnosis and
treatment of intussusception. Hepatobiliary disorders Viral
hepatitis, cholecystitis, cholangitis, gallbladder hydrops,
choledocholithiasis, and perihepatitis (Fitz-HughCurtis syndrome)
present with acute right upper quadrant or epigastric abdominal
pain. Patients with choledochal cyst experience recurrent bouts of
bil- iary obstruction, right upper quadrant pain, and a pal- pable
right upper quadrant mass. The pain associated with acute
cholecystitis and biliary pain caused by bile stones (biliary
colic) are almost indistinguishable. Patients experience dull,
persistent right upper quadrant or epigastric pain with radiation
to the right scapula. Bil- iary colic pain usually resolves within
6 hours of onset, but that of acute cholecystitis is more
persistent and is typically accompanied by low-grade fever, nausea,
vomit- ing, right upper quadrant tenderness with guarding, and
positive Murphys signthe patient stops inhaling as the inamed
gallbladder touches the palpating nger placed below the right
costal margin. Laboratory abnormalities include mild elevation of
white blood cells, serum total bilirubin, and alkaline phosphatase.
More remarkable liver test abnormalities are seen in
choledocholithisais, Mirrizzis syndrome (compression of hepatic
duct by gall- stone in the neck of the gallbladder), and acute
hepatitis. Cholangitis is characterized by a fever, chills, rigor,
right upper quadrant tenderness, jaundice, and leukocytosis.
Gallbladder hydrops can be seen with Kawasaki disease,
HenochSchoenlein purpura, and scarlet fever. Fitz- HughCurtis
syndrome has been associated with pelvic inammatory disease caused
by Neisseria gonorrhoeae and Chlamydia trachomatis. Abdominal
ultrasonography description of these disorders is beyond the scope
of this chapter. A brief discussion of the common causes follows.
Acute appendicitis Pain followed by anorexia, nausea, and
temperature ele- vation (mnemonic PANT) describes classic
progression of symptoms in appendicitis. Appendicitis is a clinical
diagnosis, supported by appropriately selected radiologi- cal and
laboratory studies. Patients with classic history and physical
ndings do not require additional studies, and urgent surgical
intervention is appropriate. White blood cell count of 20,000 per
mm3 is seen in perfo- rated appendicitis, or appendiceal abscess.
The appendix is visualized as a round structure of 7 mm in diameter
with the anechoic lumen surrounded by hyperechoic and thickened
wall (2 mm) is the classic ultrasonographic nding. The pooled
sensitivities and specicities from one meta-analysis describing use
of ultrasonography in 9356 children were 88% and 94%,
respectively.5 Helical computed tomography (CT) of the appendix is
a useful adjunct in selected patients and is a reliable method for
differentiating periappendicular phlegmon from abscess. The
sensitivity and specicity of CT for diagnosing appendicitis are 90%
and 8590%, respectively.13 Small bowel obstruction In pediatric
patients, common causes of bowel obstruc- tion are intussusception,
intestinal atresia, meconium ileus, postoperative adhesions,
malrotation with midgut volvulus, and incarcerated inguinal hernia.
Intestinal atresia and meconium ileus present in the newborn
Extra-abdominal Causes of Acute Abdomen Cardiac Myocarditis
Pericarditis Endocarditis Congestive heart failure Thoracic Lower
lobe pneumonia Pneumothorax Hematologic Sickle cell crisis Acute
leukemia HenochSchnlein purpura Vaso-occlusive crisis Metabolic
Diabetic ketoacidosis Acute adrenal insufciency Acute porphyria
Neurologic Abdominal epilepsy Abdominal migraine Herpes zoster
Nerve root compression Radiculitis Toxins/drug-related Lead
poisoning Hypersensitivity reactions Narcotic withdrawal
Miscellaneous Familial Mediterranean fever Adapted from reference
10. Table 15.
25. CHAPTER 1 Abdominal Pain 9 Carnetts sign helps in
distinguishing abdominal wall pain from visceral pain. The
diagnosis of abdomi-
nalwallpainisalsosuggestedwhenthepainissupercial, localized to a
small area, or associated with dysesthesia in the involved area.
Table 16 lists possible etiology of abdominal wall pain.More
commonly identied organic causes of chronic abdominal pain are
mentioned in Table 17. There are rare disorders affecting the
visceral and hepatobiliary scintography are useful in initial
evalu- ation of patients with hepatobiliary disorders. Acute
pancreatitis Pancreatitis is characterized by acute-onset
epigastric and upper abdominal pain, increasing rapidly in
severity. The pain sometimes radiates to the back or the left scap-
ula. Fever, nausea, anorexia, and vomiting are associated symptoms.
Flank (Grey-Turners sign) or periumbilical (Cullens sign)
ecchymoses are seen in the setting of hemorrhagic pancreatic
necrosis. Elevation of serum amylase and lipase occurs within few
hours of pain. A sentinel loop or a cut-off sign, indicating focal
ileus, may be seen on abdominal radiographs. Abdominal ultrasound
is a useful diagnostic tool for identifying cho- ledocholithiasis
as the cause for pancreatitis. Abdominal CT is indicated in severe
or complicated pancreatitis. Chronic Abdominal Pain Patients fall
under two broad groups: (a) abdominal pain due to an organic
etiology and (b) patients with FGID without identiable biochemical
or structural abnormalities. If enough tests are done, there is a
con- siderable chance of discovering some abnormality. However,
that abnormality may not be the explanation of the patients
symptoms. On the other hand, as our understanding of neurobiology
of pain, gut microbiol- ogy, and gastrointestinal inammation
improves, there may eventually be an organic explanation for some
patients with functional complaints. Etiology of Abdominal Wall
Pain Condition Features Diagnosis Abdominal wall hematoma Trauma,
laparoscopic procedure Abdominal US, abdominal CT Hernia
Protuberance in abdominal wall, decreasing in size with supine
position Abdominal US or CT, herniography Abdominal muscle tear
Occurs in athletes History and examination Herpes zoster Vesicles,
pain, hyperesthesia along a dermatome History and examination
Spinal nerve irritation Disorders of thoracic spine Spinal CT or
MRI Rectus nerve entrapment Pain along the lateral edge of rectus
sheath worsening with muscle contraction Pain relief with local
anesthetic Thoracic lateral cutaneous nerve entrapment Occurs
spontaneously following surgery History and examination
Ilioinguinal and ilio-hypogastric nerve entrapment Lower abdominal
pain after inguinal herniorrhaphy History and examination Slipping
rib syndrome Subluxation of 810th ribs causing sharp upper
abdominal pain Hooking maneuver to pull lower ribs anteriorly will
reproduce pain CT = computed tomography; MRI = magnetic resonance
imaging; Adapted from reference 19. US = ultrasound. Table 16.
Organic Causes of Chronic Abdominal Pain Gastrointestinal
Inammatory bowel disease Celiac disease Intermittent volvulus
Recurrent intussusception Chronic constipation Esophagitis (reux,
eosinophilic, infectious) Gastritis (peptic, eosinophilic,
infectious) Peptic ulcer Hernia (internal, diaphragmatic,
umbilical, inguinal) Carbohydrate malabsorption Intestinal foreign
body Parasitic infection Tumor Hepatobiliary/pancreatic
Cholelithiasis Cholecystitis Chronic or recurrent acute
pancreatitis Sphincter of Oddi dysfunction Biliary dyskinesia
Chronic hepatitis Renal/urologic Nephrolithiasis Hydronephrosis,
ureteropelvic junction obstruction Recurrent cystitis/
pyelonephritis Pelvic Hematocolpos Mittelschmerz Endometriosis
Adapted from references 10,19. Table 17.
26. 10 Section 1: Symptoms and Assessment ing may have rapid
gastric emptying with slow bowel transit.4
Esophagogastroduodenoscopy is indicated in the presence of
dysphagia, when symptoms persist despite the use of acid-reducing
medications, or become recur- rent on cessation of such
medications, and for conrma- tion of Helicobacter pylori-associated
disease. Irritable bowel syndrome A diagnosis of IBS is made when
abdominal discomfort or pain occurring at least once per week for
at least 2 months before diagnosis is associated with two or more
of the following at least 25% of the time: (a) improvement with
defecation; (b) onset associated with a change in stool frequency;
and (c) onset associated with a change in stool form. In addition,
there must be no inammatory, anatomic, metabolic, or neoplastic
abnormalities that may explain the symptoms. Other symptoms that
support the diagnosis of IBS are (1) four or more stools per day
and two or less stools per week, (2) lumpy/hard or loose/watery
stool, (3) straining, urgency, or feeling of incomplete evacuation
with stool passage, (4) presence of mucus in stool, and (5)
bloating or feeling of abdominal distension. In Western coun-
tries, 6% of middle-school students and 14% of high- school
students have IBS. Genetic predisposition, stress-
fuleventsearlyinlife,andineffectivecopingmechanisms are often
present in these patients. Various antecedents, including
inammation, intestinal trauma, allergy, or infection, could induce
visceral hypersensitivity and/or altered gut motility.4 Patients
with normal physical examination and growth and no alarm signals do
not require invasive testing for initial evaluation. Abdominal
migraine These patients have two or more paroxysmal episodes of
intense,acute periumbilical pain lasting for 1 hour or more in the
preceding 12 months before diagnosis. The pain interferes with
normal activities and is associated with two or more of the
following: anorexia, nausea, vomiting, pho- tophobia, and pallor.
Patients remain symptom-free for weeks to months in between the
paroxysmal episodes. Theremustbenoevidenceof
anyinammatory,anatomic, metabolic, or neoplastic process that may
explain the patients symptoms. This disorder is present in 14% of
children and is more common in girls than boys (3:2), with a mean
age of onset at 7 years and peak at 1012 years. Abdominal migraine,
cyclic vomiting syndrome, and migraine headache are all probably
manifestations of a single disorder. Abnormal visual-evoked
responses, abnormalities in hypothalamicpituitaryadrenal axis, and
autonomic dysfunction have been described. When appropriate,
diagnostic evaluation is done to rule out obstructive processes of
urologic or digestive system, bil- iary disorders, recurrent
pancreatitis, intracranial lesions, nerves rather than the
abdominal organs, such as acute intermittent porphyria, lead or
arsenic poisoning, and radiculopathies. Rare and obscure causes of
chronic or intermittent abdominal pain are listed in Table 18. FAP
is the most common cause of chronic or RAP in chil- dren. It is not
a diagnosis of exclusion and can be diag- nosed correctly,
utilizing symptom-based criteria, with- out resorting to a battery
of tests. These patients do not have any alarm symptoms or signs,
the physical exami- nation is normal, and stool tests are negative
for occult blood. Rome III criteria for children aged 418 years are
used for establishing the diagnosis of FGID associated with pain
(Table 19).4 The following is a brief description of childhood FAP
disorders. Functional dyspepsia A diagnosis of functional dyspepsia
is made when symp- toms of persistent or RAP centered in the upper
abdomen occur at least once per week for at least 2 months before
diagnosis. The pain is not relieved by defecation or associated
with change in stool frequency or consistency. There is no evidence
of any inammatory, anatomic, metabolic, or neoplastic process. The
prevalence of dys- pepsia among children 418 years referred to
tertiary care clinics in NorthAmerica was between 12.5% and
15.9%.14 Dyspeptic symptoms often follow a viral illness. Delayed
gastric emptying, abnormal gastric myoelectrical activity, altered
antroduodenal motility, and reduced gastric vol- ume response to
feeding have been described in children with functional dyspepsia.
Dyspeptic children with bloat- Obscure Causes of Abdominal Pain
Etiology Conrmatory tests Compressive radiculopathy CT or MRI Lead
poisoning Elevated serum lead levels Hereditary Mediterranean fever
Family history, MEFV gene mutation Acute intermittent porphyria
Elevated urine porphobilinogen Hereditary angioneurotic edema Low
levels of complement C1 inhibitor and complement C4 Narcotic
withdrawal History of narcotic use Abdominal vasculitides
Angiography, clinical features of systemic disorders such as
polyareteritis nodosa, lupus, etc. Abdominal epilepsy
Electroencephalography Abdominal migraine Diagnosis of exclusion CT
= computed tomography; MRI = magnetic resonance imaging.Adapted
from reference 19. Table 18.
27. CHAPTER 1 Abdominal Pain 11 Readers should realize that
establishing a working diagnosis of FGID and initiation of
conservative man- agement does not preclude the need for ongoing
monitoring, careful follow-up, and focused diagnostic work-ups when
indicated. DIAGNOSIS Acute Abdominal Pain History and physical
examination should determine the selection of laboratory and
radiographic studies. Observation and repeat examination at
appropriate intervals, without any studies, may be sufcient in a
well-appearing child with abdominal pain and normal physical
examination. Specic laboratory studies (Table 110) and radiographic
evaluation (Table 111) help in formulating an accurate diagnosis
and in assessing physiological status of the patient. A complete
blood count with white blood cell differential and a urinalysis
familial Mediterranean fever,and metabolic disorders such as acute
intermittent porphyria.4 Childhood functional abdominal pain FAP is
diagnosed when episodic or continuous abdomi- nal pain is present
at least once per week for at least 2 months before diagnosis.
These patients do not satisfy criteria for other FGID. There is
also no evidence of any underlying inammatory, anatomic, metabolic,
or neo- plastic process. A diagnosis of functional abdominal pain
syndrome (FAPS) is made when abdominal pain is associated with loss
of daily functioning or other somatic symptoms such as headache,
limb pain, or sleeping dif- culty. In contrast to children with
IBS, visceral hyper- sensitivity of the rectum has not been shown
in children with FAPS. This, of course, does not preclude the pos-
sibility of a more proximally located visceral hypersen- sitivity.
These patients may have lower pressure pain threshold but this
theory is yet to be validated. Symp- toms of anxiety, depression,
and somatization are often present in children with FAPS and their
parents.4 Rome III Criteria for Functional Bowel Disorders
Associated with Abdominal Pain or Discomfort in Children Functional
dyspepsia: Must include all of the following (criteria fullled at
least once per week for at least 2 months before diagnosis):
Persistent or recurrent pain or discomfort centered in the upper
abdomen (above the umbilicus) Not relieved by defecation or
associated with onset of a change in stool frequency or stool form
No evidence of an inammatory, anatomic, metabolic, or neoplastic
process that explains the subjects symptoms Irritable bowel
syndrome: Must include all of the following (criteria fullled at
least once per week for at least 2 months before diagnosis):
Abdominal discomfort (an uncomfortable sensation not described as
pain) or pain associated with two or more of the following at least
25% of the time: (a) improved with defecation; (b) onset associated
with a change in frequency of stool (four or more stools per day
and two or less stools per week); (c) onset associated with a
change in form (appearance) of stool No evidence of an inammatory,
anatomic, metabolic, or neoplastic process that explains the
subjects symptoms Childhood functional abdominal pain: Must include
all of the following (criteria fullled at least once per week for
at least 2 months before diagnosis): Episodic or continuous
abdominal pain Insufcient criteria for other functional
gastrointestinal disorders No evidence of an inammatory, anatomic,
metabolic, or neoplastic process that explains the subjects
symptoms Childhood functional abdominal pain syndrome: Must include
childhood functional abdominal pain at least 25% of the time and
one or more of the following (criteria fullled at least once per
week for at least 2 months before diagnosis): Some loss of daily
functioning Additional somatic symptoms such as headache, limb
pain, or difculty sleeping Abdominal migraine: Must include all of
the following (criteria fullled two or more times in the preceding
12 months): Paroxysmal episodes of intense, acute periumbilical
pain that last for 1 hour or more Intervening periods of usual
health lasting weeks to months The pain interferes with normal
activities The pain is associated with two or more of the
following: (a) anorexia; (b) nausea; (c) vomiting; (d) headache;
(e) photophobia; (f) pallor No evidence of an inammatory, anatomic,
metabolic, or neoplastic process that explains the subjects
symptoms Table 19.
28. 12 Section 1: Symptoms and Assessment urine analysis, stool
ova, and parasite analysis) in distin- guishing between organic and
FAP. Abnormal laboratory tests for a common intestinal disorder,
such as lactose malabsorption or H. pylori infection, may co-exist
with abdominal pain but do not necessarily establish a causal
relationship between them. Pediatric patients with H. pylori
infection are not more likely to have abdominal pain than those
without H. pylori infection. Similarly, treatment of lactose
malabsorption does not always result in clinical improvement.
Lactose malabsorption may be a trigger that unmasks visceral
hypersensitivity; it may be caused by another condition such as
celiac disease, or may simply co-exist with IBS. Similarly, there
is very little evidence that routine use of abdominal
ultrasonography in the absence of alarm symptoms has a signicant
yield of organic disease. are generally indicated in all patients
with acute abdominal pain. Measurement of serum electrolytes, blood
urea nitrogen, creatinine, and glucose levels helps in assessing
patients uid balance, acidbase status, renal function, and
physiological state. An algorithmic approach for evaluation of a
patient presenting with acute abdominal pain is shown in Figures 13
and 14. Chronic Abdominal Pain Diagnostic evaluation of the patient
with chronic abdom- inal pain is individualized based on history
and physical examination ndings. No study has evaluated the utility
of common laboratory tests (complete blood count, erythrocyte
sedimentation rate, serum electrolytes, blood urea nitrogen,
creatinine, liver enzymes, serum albumin, Radiological Imaging in
Patients with Acute Abdominal Pain Study Conditions Abdominal plain
lms Small bowel obstruction,intestinal perforation,ingested foreign
body Ultrasonography Gallstones, cholecystitis, ovarian torsion,
ectopic pregnancy, tubo-ovarian abscess, testicular torsion,
ileocolic intussusception, testicular torsion Focused abdominal
ultrasonography for trauma (FAST) Abdominal trauma (hemoperitoneum)
Upper gastrointestinal contrast series Midgut volvulus Contrast
(air or barium) enema Intussusception Computed tomography with
contrast Appendicitis,pancreatitis,intra-abdominal
abscess,intra-abdominal mass, trauma Noncontrast helical computed
tomography Urolithiasis Chest radiograph Lower lobe pneumonia,
cardiomegaly (pericarditis, myocarditis), pneumoperitoneum
Suggested radiological studies to evaluate patients with acute
abdominal pain.History and physical examination ndings determine
selection of appropriate radiographic studies. Table 111.
Laboratory Tests in Patients with Acute Abdominal Pain All patients
Complete blood count, urinalysis Postmenarchal female Urine
pregnancy test Upper abdominal pain Liver biochemical test, serum
amylase, serum lipase Abdominal pain and pharyngitis Throat swab
for rapid screen and/or culture for group A -hemolytic
streptococcus Sick-appearing, dehydrated Serum electrolytes, blood
urea nitrogen, creatinine, glucose Febrile
patients,immunocompromised patients Blood culture and/or urine
culture Bloody stool Stool culture C.difficile toxin Suggested
laboratory studies to evaluate patients with acute abdominal
pain.History and physical examination ndings determine selection of
appropriate laboratory studies. Table 110.
29. CHAPTER 1 Abdominal Pain 13 rhea, iron deciency anemia,
involuntary weight loss or deceleration of growth, elevated
sedimentation rate or C-reactive protein, extraintestinal symptoms
suggestive of inammatory bowel disease (fever, rash, arthralgia,
recurrent aphthous ulceration,and severe fatigue),local- ized right
lower quadrant pain, and perianal stula. TREATMENT Acute Abdominal
Pain Most children with acute abdominal pain have viral gas-
troenteritis or other minor illnesses. Children who are
sick-appearing and immunocompromised, and have history of abdominal
trauma, signs of bowel obstruc- tion, or evidence of peritoneal
irritation require prompt intervention and treatment. Initial
resuscitation measures include correction of hypoxemia, replacement
of intravascular volume loss, and correction of meta-
bolicabnormalities.Empiricbroad-spectrumantibiotics Diagnostic
tests are sometimes indicated in patients with severe debilitating
abdominal pain with impairment of functioning to reassure the
patient, parents, or referring physician that an organic problem is
not present. An algorithmic approach for evaluation of patients
presenting with chronic or RAP is summa- rized in Figure
15.Commonly ordered studies are sum- marized in Table 112. Invasive
tests There is no role for routine use of capsule endoscopy for the
evaluation of patients with chronic abdominal pain. Upper endoscopy
is indicated in patients with signicant dysphagia, when dyspeptic
symptoms persist despite the use of acid-reducing medications or
become recurrent on cessation of such medications, hematemesis, and
evaluation for Crohns disease, for conrmation of H.
pylori-associated disease, and for conrmation of celiac disease.
Patients with RAP may require colonoscopy in the presence of
gastrointestinal bleeding, profuse diar- FIGURE 13 Algorithmic
approach to the patient with acute abdominal pain with catastrophic
presentation, evidence of intestinal obstruc- tion, localized
abdominal tenderness, or suspicion of hepatobiliary disorder. CBC =
complete blood count; UA = urinalysis; CT = computed tomography;
RUQ = right upper quadrant; RLQ = right lower quadrant; ALT =
alanine aminotransferase; AST = aspartate aminotransferase; GGT =
-glutamyltransferase. Abdominal pain < 24 hrs Abdominal
distension, focal tenderness, and/or peritoneal sign Prostrated,
very sick appearing Severe, continuous pain Unstable vital signs
Catastrohic presentation Yes Yes Yes Yes No No No Abdominal
distension Bilious/feculent emesis Pain-periumbilical, later RLQ
Anorexia Nausea Temperature elevation RUQ, or epigastric pain
Jaundice Hepatomegaly Nausea, vomiting Abdominal plain film Urgent
surgery consult Focused abdominal sonography for trauma (FAST)
Consider abdominal CT Consider diagnostic paracentesis Emergency
laparotomy Abdominal plain film Surgery consult Ultrasound of RLQ
if intussusception suspected Possible abdominal CT Perforated
viscus Intra-abdominal hemorrhage/hematoma Bowel ischemia:
necrotizing enterocolitis, volvulus, mesenteric infarction CBC. UA
Surgical consult Ultrasound of RLQ Abdominal CT Laparotomy Amylase,
lipase Liver tests: ALT, AST, GGT, Alkaline phosphatase Ultrasound
abdomen Hepatobiliary scintigraphy Neonate: Volvulus 2 mo 2 years:
Intussusception Hirschsprung disease Incarcerated hernia > 2
years: Adhesions Acute pancreatitis Acute cholecystitis Cholangitis
Choledocholithiasis Suspicion of intestinal obstruction Suspicion
of appendicitis Suspicion of hepatobiliary disorder Diagnostic
consideration Diagnostic consideration Diagnostic
consideration
30. 14 Section 1: Symptoms and Assessment are often indicated
in immunocompromised patients and when there is clinical suspicion
of a serious intra- abdominal infection. Gastric decompression with
nasogastric suction is necessary when there is bowel obstruction.
Analgesics should be used in patients with moderate-to-severe
abdominal pain, preferably after a surgeon has been able to
evaluate the patient. Manage- ment strategies for patients with
acute abdominal pain are summarized in Figures 13 and 14. Chronic
Abdominal Pain If an organic etiology of chronic abdominal pain is
identied, disease-specic therapeutic measures are instituted.
Physicians often feel challenged and frus- trated while caring for
patients with FAP. If the patient shows poor response to treatment,
it is often perceived as a personal failure on the part of the
treating physi- cian. This sense of failure and frustration is
exacerbated by a diagnosis that seems uncertain and has no obvious
structural basis. It is extremely important for the treat- ing
physician to understand the following: FGID are a positive
diagnosis, based on clinical crite- ria (Table 113). These
syndromes are chronic, and the goal of treatment is resumption of
normal functioningnot complete eradication of abdominal pain. The
physician should reduce expectations for cure and focus on
function. The patient and his or her family must understand that
they bear signicant responsibility for disease management. This is
facilitated by the physicians empathy, support, guidance, and a
hopeful attitude. Evaluation of the patient presenting with chronic
abdominal pain is done in the context of the biopsycho- social
model of care. Psychological factors alone do not help to
distinguish between organic and FGID. Nevertheless, it is important
to identify and address the following factors: Establish an
appropriate physicianpatient relation- ship. An effective
physicianpatient relationship is the most important part of the
disease management. It is important to validate the symptoms by
acknowledg- ing the pain and its impact on the quality of life.
Pro- viding a physiological explanation helps to clarify that the
symptoms are not imagined. It is also helpful to provide clear
age-appropriate examples of conditions associated with hyperalgesia
such as chronic head- ache without intracranial pathology, or
abnormal sensation at the site of a healing scar. Examples of
interaction between the brain and the gut should be mentioned. A
good example is diarrhea or vomiting occurring during stressful
situations such as sports competition or school examinations.
Identication of the patients (and the familys) worries, concerns,
and expectations helps physicians to understand the symptoms within
a biopsychosocial context. Finally, patients and their family
members need reassurance that the symptoms are not caused by a
serious disease and do not require extremes of investigation and
intervention. Set reasonable therapeutic goals. Therapeutic goals
should be established early in the course of treat- ment. The goals
are regular school attendance, resumption of normal activities,
including participa- tion in extracurricular activities, and
reduction in the stress of a chronic disease. Obstacles to school
attend- ance (adverse school environment, negative peer
interactions, unreasonable academic expectations, and fear of a
pain episode at school) must be identi- ed and addressed. It is
important to discuss the pos- sibility of secondary gains
perpetuating the pain behavior. For example, pleasurable activities
such as watching television should not be allowed if the patient is
sick enough to miss school. It is helpful to maintain a diary
detailing the circumstances of pain episodes, aggravating factors,
and the emotional and Abdominal pain < 24 hours Poorly localized
or diffuse abdominal tenderness No peritoneal signs Low-grade
fever, diarrhea, sore throat, headache Diffuse or periumbilical
non-progressive abdominal pain Suspect viral syndrome or other
self-limiting infections Yes Lower lobe pneumonia Pericarditis
Myocardititis Testicular torsion Henoch-Schnlein purpura Pelvic
inflammatory disease Acute constipation Acute exacebation of
functional abdominal pain Abdominal migraine flare up Acute
exacerbation of irritable bowel syndrome Consider functional bowel
disorder CBC, UA Stool studies, if indicated Throat swab, if
indicated Reassessment No No Consider extra- abdominal causes
FIGURE 14 Algorithmic approach to the patient with acute abdominal
pain without peritoneal sign, localized pain, intestinal
obstruction, or catastrophic presentation. CBC = complete blood
count; UA = urinalysis.
31. 15 FIGURE 15 Suggested algorithm for the evaluation of
chronic abdominal pain. CBC = complete blood count; CMP =
comprehensive metabolic panel; CRP = C-reactive protein; EGD =
esophagogas- troduodenoscopy; ESR = erythrocyte sedimentation rate;
H. pylori = Helicobacter pylori; IBS = irritable bowel syndrome;
O&P = ova and parasite; RLQ = right lower quadrant; RUQ = right
upper quadrant; breath test; UBT = urea breath test; UGI-SBFT =
upper gastrointestinal small bowel follow-through; US = ultrasound.
Chronic abdominal pain (at least 1 episode per week for at least 2
months) EGD if associated with dysphagia, persistent, or recurrent
symptoms, for H. pylori confirmation, presence of alarm signals.
Add colonoscopy if Crohn disease is suspected UGI series for
significant vomiting Abdominal sonography, hepatobiliary
scintigraphy for RUQ pain CBC with differential ESR, CRP CMP Stool
hemoccult Stool H. pylori antigen or 13 C-UBT No alarm signals,
normal examination, and normal labs CBC with differential ESR, CRP
CMP Stool hemoccult Amylase, lipase, serum C4, urine
porphobilinogen, abdominal plain film during paroxysms UGI-SBFT
Abdominal US No alarm signals, normal examination, and normal labs
2 or more episodes in preceding 12 months Associated anorexia,
vomiting, photophobia; headache, or pallor Alarm signals:
Involuntary weight loss, growth retardation, significant vomiting,
significant diarrhea, gastrointestinal blood loss, extraintestinal
symptoms, consistent RUQ or RLQ pain, abnormal physical
examination, anemia, elevated ESR/CRP, elevated liver enzymes,
hypoalbuminemia With dyspepsia With diarrhea, or diarrhea +
constipation With constipation With pain alone With cyclical
symptoms CBC with differential ESR, CRP CMP Stool hemoccult Celiac
panel Lactose breath test Stool O&P, giardia antigen, culture,
Clostridium difficile toxin CBC with differential ESR, CRP CMP
Stool hemoccult CBC with differential ESR, CRP CMP Stool hemoccult
Celiac panel EGD if celiac disease suspected Add colonoscopy if
alarm signals present and infectious etiology excluded Endoscopy
considered in presence of alarm signals, or if pain continues to
severely affect lifestyle for reassurance Endoscopy indicated in
rare situations in presence of alarm signals, or for celiac disease
work-up No alarm signals, normal examination and normal labs
Functional abdominal pain syndrome No alarm signals, normal
examination, and normal labs No alarm signals, normal examination,
and normal labs Consider gastric emptying scan, antroduodenal
motility studies in selected patients Functional dyspepsia IBS IBS
Evidence of fecal retention Functional constipation Functional
abdominal pain Loss of daily functioning, somatic symptoms
Abdominal migraine
32. 16 Section 1: Symptoms and Assessment Identify and modify
triggers of pain. It is important to identify and possibly reverse
physiological and psy- chosocial stress factors that trigger,
exacerbate, and perpetuate chronic pain. Dyspeptic symptoms may be
associated with gastroesophageal reux, delayed gas- tric emptying,
or altered gastrointestinal motility. Other concurrent
physiological processes that may trigger pain include celiac
disease, constipation, lac- tose intolerance, H. pylori gastritis,
aerophagia, spicy food, or exposure to various medications. Chronic
use of laxatives, narcotic medications, and nonsteroidal
anti-inflammatory drugs must be identified and eliminated when
present. Psychosocial stress factors often include parental
separation, death in the family, a recent change of school or
residence, family mem- bers with signicant handicap or illness,
altered peer interactions, problems at school, or breakup of a
romantic relationship. Identication of these stressors helps in
reducing environmental reinforcement of pain behavior. Parents,
teachers, and other caregivers are advised to support the child
rather than focusing exclusively on the pain. A reasonable timeline
for completion of schoolwork accrued during school absence should
be negotiated with the school ofcials. If the child feels
overwhelmed with the completion of missed assignments, a reduction
of the workload may become necessary. The school ofcials must
respond to the pain behavior with empathy and work with the child
so that the school attendance or class activities are not
disrupted. A child missing school often is caught in a vicious
cycle of anxiety regarding accumu- lated schoolwork, anticipation
of pain, reduced threshold of pain due to anxiety, and increased
dis- tress. A rapid return to school is extremely important.
Psychiatric referral must be done if maladaptive family-coping
mechanisms are identified or the patient demonstrates symptoms of
anxiety disorder, panic disorder, or depression. Disease
exacerbations that are clearly attributable to psychological
distress are often amenable to psychological interventions. In
casesunresponsivetothesecommon-senseapproaches, use of central
analgesics (tricyclic antidepressants (TCAs) or
serotoninnorepinephrine reuptake inhib- itors (SNRIs)) may be
considered. Dietary modications. The role of dietary modica- tion
in patients with chronic abdominal pain and FGIDs is not well
validated. If there are obvious trig-
gerssuchasspicyfoods,caffeine,carbonatedbeverages, lactose, fatty
foods, and gas-forming foods (legumes and vegetables of the cabbage
family), attempts could be made to reduce or eliminate their
intake.In patients with functional dyspepsia and postprandial symp-
toms, a trial of frequent small meals or eating low-fat meals may
be helpful. Increasing ber intake may benet patients with both
diarrhea-predominant and cognitive responses.An understanding of
the patients style of coping, severity of symptoms, and degree of
disability helps in devising appropriate treatment strategies.
Pharmacotherapy for Functional Gastrointestinal Disorders Diagnosis
drugs Functional dyspepsia H2 blockers: famotidine, ranitidine PPI:
esomeprazole, lansoprazole, omeprazole, pantoprazole Prokinetics:
erythromycin, metoclopramide IBS peppermint oil* , dicyclomine,
hyoscyamine FAP(S) TCA: amitriptyline# , desipramine SNRI:
duloxetine, venlafaxine Abdominal migraine cyproheptadine,
pizotifen, propranolol, sumatriptan There are no well-validated
published controlled trials on efcacy and their doses of these
pharmacological agents in pediatric patients with functional
gastrointestinal disorders.FAP(S) = functional abdominal pain
(syndrome); H2 = histamine 2; IBS = irritable bowel syndrome; PPI =
proton pump inhibitor; SNRI = serotoninnorepinephrine reuptake
inhibitor;TCA = tricyclic antidepressant. *Peppermint oil
enteric-coated capsule (187 mg) dose: 3045 kg,one capsule three
times daily; 45 kg,two capsules three times daily. #Suggested dose
of amitriptyline: 0.25 mg/kg/day and slowly titrated up to 1
mg/kg/day. Table 113. Laboratory and Imaging Studies in Patients
with Chronic Abdominal Pain All patients CBC, CMP, ESR, UA, IgA
tissue transglutaminase Diarrhea Stool O&P, C.difficile
culture, lactose breath hydrogen test RUQ, or RLQ pain, cyclic
symptoms, abdominal mass Abdominal ultrasound, abdominal and pelvic
CT with contrast, UGI-SBFT Dyspepsia, vomiting UGI, gastric
emptying scintigraphy, 13C-UBT or stool for H.pylori antigen
Hepatobiliary scintigraphy with CCK Suggested laboratory and
imaging studies in patients with chronic abdominal pain based on
clinical presentation.CBC = complete blood count; CCK =
cholecystokinin; CMP = comprehensive metabolic panel; ESR =
erythrocyte sedimentation rate; O&P = ova and parasite; RLQ =
right lower quadrant; RUQ = right upper quadrant; UA = urine
analysis; UBT = urea breath test; UGI-SBFT = upper gastrointestinal
small bowel follow-through. Table 112.
33. CHAPTER 1 Abdominal Pain 17 patients with visceral pain.
These agents probably act by depressing abnormal neuronal
discharges and raise the inappropriately lowered pain threshold of
sensitized neurons. These agents must be used with caution because
the pediatric experience is limited and the vis- ceral pain
indication is off-label. Similarly, no controlled trial has been
conducted in the pediatric population to study the efcacy of anti-
cholinergic agents such as dicyclomine (bentyl) and hyoscyamine
(Levbid and Levsin).However,these agents are commonly prescribed.
The presumed clinical benet is from smooth muscle relaxation due to
blockage of muscarinic effects of acetylcholine on gastrointestinal
tract. Patients must be cautioned about blurred vision, drowsiness,
dry mouth, tachycardia, constipation, and urinary retention when
these agents are used. Peppermint oil is an antispasmodic agent
that relaxes intestinal smooth muscle by decreasing calcium inux
into the smooth muscle cells. Enteric-coated pep- permint oil
capsules (Colpermin) had a greater efcacy than placebo in reducing
functional pain in a random- ized double-blind controlled trial
consisting of pediat- ric patients with IBS. There are no
evidence-based data on the efcacy of antidiarrheal agents such as
loper- amide and diphenoxylate, and bile salt binding agent
cholestyramine in patients with diarrhea-predominant IBS.
Polyethylene glycol 3350 is useful in treating con- stipation in
patients with constipation-predominant IBS. Fiber supplements such
as psyllium, methylcellu- lose, polycarbophil, wheat dextrin, and
inulin are effective in treating symptoms of both diarrhea and
constipation. Prophylactic agents that are used for abdominal
migraine are pizotifen, propranolol, cypro- heptadine, and
sumatriptan.4,15,16 Psychological treatment. Psychological
treatments such as hypnotherapy and cognitivebehavioral therapy
(CBT) have been shown to be effective in treating somatic symptoms
of adult patients with FGIDs. There are also emerging data from
randomized trials about the effectiveness of these interventions
among children and adolescents with FAP or IBS. These tech- niques
promote the patients ability to self-manage symptoms. Goals of CBT
are to identify maladaptive thoughts, perceptions, and behaviors,
improve coping and functioning, improve communication and prob- lem
solving, and develop ways to improve symptom control. These goals
are achieved by modifying dys- functional cognition, abnormal
behavior, and errone- ous assumptions or beliefs. Stress management
and relaxation techniques such as progressive muscle relax- ation
and controlled breathing can be used to alter pain perception by
counteracting physiological effects of stress and anxiety.
Gut-directed hypnotherapy constipation-predominant IBS and FAP. The
recom- mended amount of daily ber intake (in grams) is estimated in
children by adding 5 to the patients age. Patients with excessive
atulence may benet from avoidance of sorbitol containing chewing
gum, car- bonated beverages, legumes, and foods of the cabbage
family. A sudden increase in daily ber intake may lead to increased
colonic gas production, abdominal distension, and worsening
abdominal pain. Pharmacotherapy. Published controlled trials
regard- ing the efficacy of pharmacological agents for management
of FGIDs are rare. Evidence of efcacy to be greater than placebo
has been shown for famoti- dine for functional dyspepsia, pizotifen
for abdominal migraine, and peppermint for IBS. Sedatives and anx-
iolytics are generally not effective, carry the risk of causing
sedation and addiction, and have been shown to have no effect on
bowel and sensory symptoms in human control subjects. In patients
with functional dyspepsia, antisecretory medications such as H2
blockers or proton pump inhibitors and prokinetic agents
(metoclopramide,erythromycin,and domperi- done and cisapride where
available) are often offered. The use of these therapeutic
modalities has not been validated by controlled trials, and
treatment should not be prolonged in the absence of improvement.
Antidepressants such as TCAs (e.g., desipramine, nortriptyline,and
amitriptyline) and SNRIs (e.g.,dulox- etine and venlafaxine) have
effects on central and peripheral nervous systems, and are useful
for treating chronic pain syndromes because of their combined
noradrenergic and serotonergic effects. The clinical benet could
also be due to anticholinergic effects, slow- ing of
gastrointestinal transit, fundic relaxation, restora- tion of
normal sleep pattern, treatment of comorbid depression, and
analgesic effects on receptors through- out the pain transmission
system. Physicians must emphasize that these medications are
central analge- sics, have independent effects on pain, and can be
used in lower dosages than are used to treat depression. To assure
daily use and adherence, patients and families need to be informed
that these medications are not addicting and can be stopped when
needed without major withdrawal effects. Amitriptyline has been
studied in pediatric patients, but without any placebo-controlled
evidence. A starting dose of 0.25 mg/kg/day, titrated to a maxi-
mum of 1 mg/kg/day over 810 weeks, is generally rec- ommended for
amitriptyline therapy. In older patients, alternate medications
include desipramine (2575 mg/day) or duloxetine (30 mg/day). There
are anecdotal reports of other medications, including phenytoin,
car- bamezepine, gabapentin, pregabalin, lamotrigine, topi- ramate,
zonisamide, and levetiracetam, benefiting
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2003:781. and guided imagery focus attention away from the somatic
symptoms, modify sensory experience, enhance feelings of
mastery/self-control, and reduce distress. Biofeedback uses a
computer-generated visual or auditory indicator of muscle tension,
skin tem- perature, or heart rate and allows the patient to vali-
date the physiological changes induced by controlled breathing,
relaxation, or hypnotic techniques.16,17 The referring physicians
role is to help the patient and his family understand the value of
these psychological treatments as part of their overall care. The
multicomponent treatment of patients with FAP is summarized in
Figure 16. Patients with severe symptoms will need combined
pharmacological and behavioral intervention. PROGNOSIS AND CLINICAL
COURSE Most patients do well after the diagnosis of FAP, with
subsequent follow-up rarely identifying an organic dis- order. Once
the child and parents are reassured that the origin of the pain is
not organic and the diagnosis of FAP is accepted, symptom
resolution or improvement occurs in 3050% of patients by 26 weeks
after diagno- sis. Approximately one-third of children with FAP
will continue to experience abdominal pain, or develop symptoms of
chronic headache, backache, and men- strual irregularities as
adults. Adverse prognostic factors described by Apley and Hale are
male sex, age of onset at 6 years, a strong history of a painful
family, and symptom duration of >6 months prior to the diagnosis
of FAP.18 FIGURE 16 Treatment algorithm for functional abdominal
pain syndrome (FAPS). Multicomponent treatment of FAPS begins with
establishment of effective physicianpatient rela